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Prediction of biodiversity - regression of lichen species richness on remote sensing data

Community Ecology 2004年第1期5卷 121-133页

作者： Waser, L.T. Stofer, S. Schwarz, M. Küchler, M. Ivits, E. Scheidegger, C. Department of Landscape Inventories WSL Swiss Federal Research Institute Birmensdorf 8903 Zürcherstrasse 111 Switzerland WSL Swiss Federal Research Institute Birmensdorf 8903 Zücherstrasse 111 Switzerland Freiburg University Department of Remote Sensing LIS Freiburg 70106 Tennenbacherstr. 4 Germany

The objective of the present study was to develop a model to predict lichen species richness for six test sites in the Swiss Pre-Alps following a gradient of land use intensity combining airborne remote sensing data and regression models. This study ties in with the European Union Project BioAssess which aimed at quantifying patterns in biodiversity and developing "Biodiversity Assessment Tools" that can be used to rapidly assess biodiversity. For this study, lichen surveys were performed on a circular area of 1 ha in 96 sampling plots in the six test sites. Lichen relevés were made on three different substrates: trees, rocks and soil. In the first step, ecologically meaningful variables derived from airborne remote sensing data were calculated using two levels of detail. 1^st level variables were processed using both spatial and spectral information of the CIR orthaimages. 2^nd level variables - based on 1^st level variables - were implemented using additional lichen expert knowledge. In the second step, all variables were calculated for each sampling plot and correlated with the different lichen relevés. Multiple linear regression models were built, containing all extracted variables, and a stepwise variable selection was applied to optimize the final models. The predictive power of the models (correlation between predicted and measured diversity) in a reference data set can be regarded as good. The obtained r ranging from 0.48 for lichens on soil to 0.79 for lichens on trees can be regarded as satisfactory to good, respectively. The accuracy of models could be further improved by adapting the model and by using additional calibration data and sampling plots. Species richness for each pixel within the six test sites was then calculated. This ecological modeling approach also reveals two main restrictions: 1) this method only indicates the potential presence or absence of species, and 2) the models may only be useful for calculating sp

关键词： Biodiversity CIR orthoimages Landscape ecology Lichens linear regression models Remote sensing

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An alternative optimization model and robust experimental design for the Assignment Scheduling Capability for the Unmanned Aerial Vehicles (ASC-U) simulation

An alternative optimization model and robust experimental de...

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作者： Oliver, Derek M. U. S. Naval Postgraduate School

学位级别：硕士

The Modeling, Virtual Environments, and Simulations Institute (MOVES) and the United States Army Training and Doctrine Command (TRADOC) Analysis Center (TRAC) at the Naval Postgraduate School, Monterey, California, developed the Assignment Scheduling Capability for Unmanned Aerial Vehicles (ASC-U) discrete event simulation to aid in the analysis of future U. S. Army Unmanned Aerial Vehicle (UAV) requirements. TRAC selected ASC-U to provide insight into the programmatic decisions addressed in the U. S. Army UAV-Mix Analysis that directly affects future development and fielding of UAVs to include the Future Combat System. ASC-U employs a discrete event simulation coupled with the optimization of a linear objective function. At regular intervals, ASC-U obtains an optimal solution to an assignment problem that assigns UAVs to mission requirements that are available or will be available at some time in the future. This thesis presents an alternative optimization model, explores 23 simulation factors, and provides sensitivity analysis for how UAV coverage may degrade in the presence of adverse random events. Integer programming, experimental design, and an innovative Optimized Flexible Latin Hypercube (OFLH) design are used to evaluate a representative sample from an Army 2018 scenario. The conclusions suggest the following: the alternative optimization model developed in this thesis can successfully maximize ASC-U value without the use of a heuristic; smaller optimization intervals do not guarantee higher total value when the heuristics are included; to maximize total value, Early Return should be set to FALSE and Secondary Areas should be set to TRUE; an OFLH is valuable for robust analysis of simulation models containing many factors; and as the model factors change over predefined ranges, the solution quality is consistent.

关键词： Integer Programming Latin Hypercube Designs Design of Experiments linear regression models Simulation Analysis Unmanned Aerial Vehicles Discrete Event Simulation Future Combat Systems UAV Optimization Optimized Flexible Latin Hypercubes Nearly Orthogonal Latin Hypercubes Stochastic Interactive Simulation

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Data-based design of robust fault detection and isolation residuals via LASSO optimization and Bayesian filtering

Data-based design of robust fault detection and isolation re...

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Asian Journal of Control

作者： Cascianelli, Silvia Costante, Gabriele Crocetti, Francesco Ricci, Elisa Valigi, Paolo Luca Fravolini, Mario Department of Engineering University of Perugia Perugia Italy

In this paper, a data-based approach for the design of structured residual subsets for the robust isolation of sensor faults is proposed. linear regression models are employed to estimate faulty signals and to build a set of primary residuals. L1-regularized least squares estimation is used to identify model parameters and to enforce sparsity of the solutions by increasing the regularization weight. In this way, it is possible to generate a set of residuals generators with different fault sensitivity. Then, a residual selection procedure based on fault sensitivity maximization is proposed to extract a minimum size subset of structured residuals that allows for isolation of the faulty sensor. To overcome modelling uncertainty, a robust recursive Bayesian Filter has been employed to process, online, the distance of the residuals from nominal fault directions, providing a fault probability for each sensor. The proposed method has been validated by designing and testing a fault isolation scheme for six aircraft sensors using multi-flight experimental data of a P92 Tecnam aircraft. © 2020 Chinese Automatic Control Society and John Wiley & Sons Australia, Ltd

关键词： Uncertainty analysis Aircraft Fault detection regression analysis Bayesian filtering Fault isolation scheme Fault probabilities L1 regularized least squares linear regression models Robust fault detection and isolation Selection procedures Structured residuals

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The quest for a triplet ground-state alkene: Highly twisted CC double bonds

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JOURNAL OF PHYSICAL ORGANIC CHEMISTRY 2019年第9期32卷 e3965-e3965页

作者： Wu, Judy I. Hommes, Nico J. R. van Eikema Lenoir, Dieter Bachrach, Steven M. Univ Houston Dept Chem Houston TX 77004 USA Friedrich Alexander Univ Erlangen Nurnberg Dept Chem & Pharm Comp Chem Ctr Erlangen Germany Helmholtz Ctr Munchen Mol Expos Neuherberg Germany Monmouth Univ Sch Sci 400 Cedar Ave West Long Branch NJ 07764 USA

Density functional theory and extrapolated CCSD(T) computations of several "anti-Bredt" alkenes were carried to explore possible 1,2-diyl "alkene" candidates with a triplet ground state. Ten candidates containing twisted double bonds at the bridgehead positions of bicyclic structures (1-6) or adamantene (7-10) derivatives were studied. Based on a combination of ring strain, rigid scaffolding, and steric crowding, four species were identified to have surprisingly low singlet-triplet energy gaps (lower than 4 kcal/mol). A tert-butyl substituted bicyclic structure (4) was identified to have a near-zero singlet-triplet energy gap, but no triplet ground-state alkene was found. Ring strain energy (RSE) calculations, pi-orbital axis vector (POAV) analyses, and multiple linear regression models were performed to elucidate the geometric and energetic effects of double bond twisting in 1-10. Based on our computational exploration, it appears unlikely that there is a ground-state triplet olefin.

关键词： anti-Bredt alkenes linear regression models singlet-triplet gaps twisted alkenes

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Improving Diesel Engine Reliability Using an Optimal Prognostic Model to Predict Diesel Engine Emissions and Performance Using Pure Diesel and Hydrogenated Vegetable Oil

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EKSPLOATACJA I NIEZAWODNOSC-MAINTENANCE AND RELIABILITY 2023年第4期25卷

作者： Zvirblis, Tadas Hunicz, Jacek Matijosius, Jonas Rimkus, Alfredas Kilikevicius, Arturas Geca, Michal Vilnius Univ Inst Data Sci & Digital Technol Vilnius Lithuania Lublin Univ Technol Fac Mech Engn Lublin Poland Vilnius Gediminas Tech Univ Inst Mech Sci Fac Mech Vilnius Lithuania Vilnius Gediminas Tech Univ Dept Automobile Engn Vilnius Lithuania

The reliability of internal combustion engines becomes an important aspect when traditional fuels with biofuels. Therefore, the development of prognostic models becomes very important for evaluating and predicting the replacement of traditional fuels with biofuels in internal combustion engines. The models have been made to model AVL 5402 engine emission, vibration, and sound pressure parameters using a three-stage statistical regression models. The fifteen parameters might be accurately predicted by a single statistic presented here. Both fuel type (diesel fuel and HVO) and engine parameters that can be adjusted were considered, since this analysis followed the symmetry of the methods. The data analysis process included three distinct steps and symmetric statistical regression testing was performed. The algorithm examined the effectiveness of various engine settings. Finally, the optimal fixed engine parameter and the optimal statistic were used to construct an ANCOVA model. The ANCOVA model improved the accuracy of prediction for all fifteen missing parameters.

关键词： engine's reliability statistical regression analysis linear regression models ANCOVA MAPE hydrotreated vegetable oil

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linear regression Analysis and Techno-Economic Viability of an Air Source Heat Pump Water Heater in a Residence at a University Campus

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ENERGIES 2021年第8期14卷 2280-2280页

作者： Manyi-Loh, Christy E. Sikhonza, Mandlenkosi Tangwe, Stephen Univ Ft Hare Ft Hare Inst Technol Fac Sci & Agr PB X1314 ZA-5700 Alice South Africa Univ Ft Hare Fac Sci & Agr Dept Phys PB X1314 ZA-5700 Alice South Africa

This study quantifies the potential of a 4.0 kW air source heat pump (ASHP) unit retrofitted to a 12.0 kW, 1000 L electric boiler coupled to a 1000 L storage tank. A data acquisition system was built to monitor the performance of the electric boiler and the ASHP water heater. The annual electrical energy saving and the load factor reduction from the electric boiler because of the ASHP unit retrofit was 34,805.94 kWh and 0.124. The net present value payback period of the ASHP system was 1.60 years. A Wilcoxon rank sum test was employed to compare both the volumes of hot water and electrical energy consumed by the two systems. linear regression models of the daily volumes of hot water and electrical energy consumed by both systems were established. The results should be of great value to the management of universities that are considering energy-efficient interventions with a significant return on investment.

关键词： electric boiler air source heat pump (ASHP) energy saving energy factor net present value payback period linear regression models Wilcoxon rank sum test

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Estimating the probability of accidents on building scaffoldings

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SAFETY SCIENCE 2022年第0期152卷 1页

作者： Nowobilski, Tomasz Hola, Bozena Wroclaw Univ Sci & Technol Fac Civil Engn Dept Mat Engn & Construct Proc PL-50370 Wroclaw Poland

The aim of the research that was conducted and presented in the article was to estimate the posterior probability of occupational accidents involving scaffoldings. The research was conducted in five regions of Poland. The authors' original research methodology was developed, which used: the results of empirical research involving the counting of scaffoldings used in selected representative areas of the studied regions;information concerning the number of occupational accidents involving scaffoldings, which was obtained from the District Inspectorates of the National Labour Inspectorate;and also data from publications of the Central Statistical Office concerning socio-economic indicators characterizing the surveyed regions. The main element of the developed methodology involved multivariate linear regression models, which were used to predict the number of scaffoldings in each studied region. The quantitative analysis of the identified accidents, in conjunction with the estimated population of scaffoldings, allowed for the estimation of the incidence rate of the occurrence of an accident involving scaffolding with regards to all the used construction scaffoldings. In this way, the incidence rates of accidents involving scaffoldings W, which indicate how many accidents occur for every 10,000 used scaffoldings, were obtained. The average value of the W index for the analyzed period of time and the five analyzed regions of the country amounted to 1.89. This means that for every 10,000 used scaffoldings, approximately two accidents may have occurred, which is equivalent to a minimum of two injured people. The obtained results of research and analyses show the scale of the phenomenon of accidentality that is related to the use of scaffolding in the studied regions. They constitute the basis for comparing regions in terms of occupational safety on scaffolding. They can also be used to predict the probability of an accident in the future. The acquired knowledge can be used

关键词： Scaffolding Occupational safety Prediction of the number of scaffoldings Probability of an accident linear regression models

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A Microfluidic 3D-Tumor-Spheroid Model for the Evaluation of Targeted Therapies from Angiogenesis-Related Cytokines at the Single Spheroid Level

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ADVANCED HEALTHCARE MATERIALS 2024年第31期13卷 e2402321页

作者： Liu, Mengqi Wang, Yihe Wang, Chao Li, Ping Qiu, Jiaoyan Yang, Ningkai Sun, Mingyuan Han, Lin Shandong Univ Inst Marine Sci & Technol Tsingdao 266237 Peoples R China Shandong Engn Res Ctr Biomarker & Artificial Inte Jinan 250100 Peoples R China

Angiogenesis is a key player in drug resistance to targeted therapies for breast cancer. The average expression of angiogenesis-related cytokines is widely associated with the treatments of target therapies for a population of cells or spheroids, overlooking the distinct responses for individuals. In this work, a highly integrated microfluidic platform is developed for the generation of monodisperse multicellular tumor spheroids (MTSs), drug treatments, and the measurement of cytokines for individual MTSs in a single chip. The platform allows the correlation evaluation between cytokine secretion and drug treatment at the level of individual spheroids. For validation, quantities of six representative proangiogenic cytokines are tested against treatments with four model drugs at varying times and concentrations. By applying a linear regression model, significant correlations are established between cytokine secretion and the treated drug concentration for individual spheroids. The proposed platform provides a high-throughput method for the investigation of the molecular mechanism of the cytokine response to targeted therapies and paves the way for future drug screening using predictive regression models at the single-spheroid level.

关键词： angiogenesis-related cytokines linear regression models microfluidic platform single spheroids targeted drugs

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The tree based linear regression model for hierarchical categorical variables

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EXPERT SYSTEMS WITH APPLICATIONS 2022年 203卷

作者： Carrizosa, Emilio Mortensen, Laust Hvas Morales, Dolores Romero Sillero-Denamiel, M. Remedios Univ Seville Dept Estadist Invest Operat Seville Spain Inst Matemat Univ Sevilla IMUS Seville Spain Stat Denmark Copenhagen Denmark Univ Copenhagen Dept Publ Hlth Copenhagen Denmark Copenhagen Business Sch Dept Econ Frederiksberg Denmark Trinity Coll Dublin TCD Sch Comp Sci & Stat Dublin Ireland

Many real-life applications consider nominal categorical predictor variables that have a hierarchical structure, e.g. economic activity data in Official Statistics. In this paper, we focus on linear regression models built in the presence of this type of nominal categorical predictor variables, and study the consolidation of their categories to have a better tradeoff between interpretability and fit of the model to the data. We propose the so-called Tree based linear regression (TLR) model that optimizes both the accuracy of the reduced linear regression model and its complexity, measured as a cost function of the level of granularity of the representation of the hierarchical categorical variables. We show that finding non-dominated outcomes for this problem boils down to solving Mixed Integer Convex Quadratic Problems with linear Constraints, and small to medium size instances can be tackled using off-the-shelf solvers. We illustrate our approach in two real-world datasets, as well as a synthetic one, where our methodology finds a much less complex model with a very mild worsening of the accuracy.

关键词： Hierarchical categorical variables linear regression models Accuracy vs model complexity Mixed integer convex quadratic problem with linear constraints

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Conductive sapwood area prediction from stem and canopy areas-allometric equations of Kalahari trees, Botswana

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ECOHYDROLOGY 2017年第6期10卷 n/a-N.PAG页

作者： Lubczynski, Maciek W. Chavarro-Rincon, Diana C. Rossiter, David G. Univ Twente Fac Geoinformat Sci & Earth Observat POB 217 NL-7500 AE Enschede Netherlands Ambient Sensing Enschede Netherlands Cornell Univ Sect Soil & Crop Sci Ithaca NY USA ISRIC World Soil Informat Wageningen Netherlands

Conductive sapwood (xylem) area (Ax) of all trees in a given forested area is the main factor contributing to spatial tree transpiration. One hundred ninety-five trees of 9 species in the Kalahari region of Botswana were felled, stained, cut into discs, and measured to develop allometric equations predicting Ax from estimates of stem (As) and canopy (Ac) areas. Stem discs were also subjected to laboratory-based computed tomography, which well detected wood density contrasts but was not diagnostic with regard to delineation of Ax. The staining experiment, along with the help of visual and computed tomography analysis, allowed the definition of 4, tree-species categories of Ax, C1-C4. In C1 (Acacia erioloba, Terminalia sericea, and Burke Africana), the staining and visual delineation of Ax matched the natural color difference between sapwood and heartwood;in C2 (Dichrostachys cinerea and Ochna pulchra), sapwood was divided into external conductive and internal nonconductive annuli;in C3 (Acacia fleckii and Acacia luederitzii), sapwood had sharp staining boundary between external highly conductive and internal low-conductive annuli;and in C4 (Lonchocarpus nelsii and Boscia albitrunca), stems had no heartwood. Per-species 0-intercept linear regression models, Ax = slope. As (slope = 0.392 divided by 0.794;R-2 = 96.7 divided by 99.8%) and Ax = slope. Ac (slope = 1.477 divided by 17.044;R-2 = 82.1 divided by 92.2%) yielded excellent to good predictive allometric equations. The first equation is suitable for Ax scaling of small-size Kalahari areas, where the As of all trees can be estimated on the ground, whereas the second, as contribution to automated tree transpiration mapping of large-size Kalahari areas, where the Ac of trees can be derived through remote sensing interpretation of high-resolution images.

关键词： allometric equations conductive sapwood area CT method cut and dye method Kalahari linear regression models

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